In the art of making tire components, plasticizers have been used to provide, among other benefits, improved gripping force on a snow or ice surface. The plasticizers can also be employed to improve compound processing characteristics. For example, low-temperature ester-type plasticizers, such as octyl oleate, have been employed as to achieve improved gripping force on a snow or ice surface, as disclosed in U.S. Pat. No. 4,567,928.
In an effort to use a larger amount of renewable, sustainable, or environmentally-friendly materials in the manufacture of pneumatic tires, recent efforts have been made to use plasticizers that are derived from natural materials. For example, U.S. Pat. No. 7,253,225 teaches the use of a plasticizing compound comprising at least one vegetable oil; U.S. Publication No. 2011/0112213 teaches a plasticizer produced via at least one biomass-to-liquid process; Publication No. WO 2013/172699 discloses a plasticizer derived from epoxidized palm oil containing not more than 2% oxirane oxygen content for use in the production of motorcycle tire treads; U.S. Pat. No. 7,371,791 discloses a terpene (co)polymer plasticizer derived from resources other than petroleum; and U.S. Publication No. 2010/0252162 discloses an epoxidized soy bean oil plasticizer.
While the prior art contemplates the use of these plasticizers derived from natural materials, tire components made using such plasticizers continue to suffer from poor performance at lower temperatures. Thus, there is a need in the art for a vulcanizable composition that can be used to make tire components, particularly tire treads, having improved low temperature performance.